$-3fg + 6fh + 2f - 5 = -3g - 7$ Solve for $f$.
Solution: Combine constant terms on the right. $-3fg + 6fh + 2f - {5} = -3g - {7}$ $-3fg + 6fh + 2f = -3g - {2}$ Notice that all the terms on the left-hand side of the equation have $f$ in them. $-3{f}g + 6{f}h + 2{f} = -3g - 2$ Factor out the $f$ ${f} \cdot \left( -3g + 6h + 2 \right) = -3g - 2$ Isolate the $f$ $f \cdot \left( -{3g + 6h + 2} \right) = -3g - 2$ $f = \dfrac{ -3g - 2 }{ -{3g + 6h + 2} }$ We can simplify this by multiplying the top and bottom by $-1$. $f= \dfrac{3g + 2}{3g - 6h - 2}$